The World Anti-Doping Agency acknowledges it knew of doping concerns involving 23 Chinese swimmers before the 2021 Tokyo Games but failed to alert others. Some of those swimmers later won gold medals.

The Court of Arbitration for Sport begins a hearing Tuesday into the doping scandal of Russian figure skater Kamila Valieva. U.S. skaters still haven't received team medals from the 2022 Winter Games.

The usually much-discussed topic hasn't been making headlines during the Tokyo Games as often because of the pandemic. But it's still there.